A 55‑yeаr‑оld client recоvering frоm surgery for а femur frаcture suddenly develops tachycardia and tachypnea. A pulmonary embolism is suspected, and the client has been placed on high‑flow oxygen. Despite initial interventions, the nurse notices a drop in cardiac output and decreasing oxygen saturation. Which finding would indicate the client is entering the progressive stage of shock?